From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Shrinking the C core Date: Sun, 20 Aug 2023 22:14:34 +0300 Message-ID: <835y59wmp1.fsf@gnu.org> References: <20230809094655.793FC18A4654@snark.thyrsus.com> <87fs4pkkqi.fsf@dataswamp.org> <87jztzkgct.fsf@dataswamp.org> <87y1if8j8t.fsf@linux-m68k.org> <87y1ifi9fv.fsf@dataswamp.org> <87zg2uqdmv.fsf@localhost> <87edk3gbh3.fsf@dataswamp.org> <87jztvnuyb.fsf@localhost> <875y5bdutt.fsf@dataswamp.org> <87y1i6e1uh.fsf@localhost> <874jkub40o.fsf@dataswamp.org> <87jztqdw2l.fsf@localhost> <87msym9i4r.fsf@dataswamp.org> <877cpp914t.fsf@localhost> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="26139"; mail-complaints-to="usenet@ciao.gmane.io" Cc: ams@gnu.org, incal@dataswamp.org, emacs-devel@gnu.org To: Ihor Radchenko Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Aug 20 21:14:50 2023 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qXnsv-0006cR-OU for ged-emacs-devel@m.gmane-mx.org; Sun, 20 Aug 2023 21:14:49 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qXnsS-0000rT-Uj; Sun, 20 Aug 2023 15:14:20 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qXnsR-0000rC-9N for emacs-devel@gnu.org; Sun, 20 Aug 2023 15:14:19 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qXnsP-0006UY-VJ; Sun, 20 Aug 2023 15:14:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=YUV4zL6I6uSFrpn9jKx2UStSB/UYixfKLSNOYVp9k04=; b=jld7/zQyZD+r Xt5ASGvRTtDsvjldrFT56GxSakAENJuF0+uZH/yFuRhzuHAl2Kiy5r8hNYIc56RjVB4wmtfl0SCIQ xKq8omY48V5rfxBw0zsn2snHSOrd9EQGZMH7T3W6dcReFiBw1pTm7Z29YYG0Y5TNk2ft3+nXVPEIl w4R+QDuserD0m/Ez6z0QIlHNleR4YpQGvqJwRgZpoilm0HyEM3OlwqNJ1sK4TDd19MwV1RcOhe+1s eAHWfriKOuzdY2wv77Npv7F1Xepbqkugys+Eh9ZFGPlDKyyVXpKTFSoZuWdWarlHd5rbVcI8TOPEL rRWqF0ABPnOFFgzvIlqk1w==; In-Reply-To: <877cpp914t.fsf@localhost> (message from Ihor Radchenko on Sun, 20 Aug 2023 15:36:34 +0000) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:308986 Archived-At: > From: Ihor Radchenko > Cc: Emanuel Berg , emacs-devel@gnu.org > Date: Sun, 20 Aug 2023 15:36:34 +0000 > > I am asking genuinely because `car' (1) has dedicated opt code and thus > should be one of the best-optimized function calls on Elisp side; (2) > Fcar is nothing but > > /* Take the car or cdr of something whose type is not known. */ > INLINE Lisp_Object > CAR (Lisp_Object c) > { > if (CONSP (c)) > return XCAR (c); // <- XCONS (c)->u.s.car > if (!NILP (c)) > wrong_type_argument (Qlistp, c); > return Qnil; > } 'car' does have a dedicated bytecode op-code, but that op-code simply calls XCAR, exactly like Fcar and CAR above do: CASE (Bcar): if (CONSP (TOP)) TOP = XCAR (TOP); else if (!NILP (TOP)) wrong_type_argument (Qlistp, TOP); NEXT;